In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The first phase of Earth MRI focuses on the study of rare-earth elements (REE). The USGS has identified broad areas within the U.S. to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of REE potential in these areas. Focus areas were defined using existing geologic data on known REE deposits in the U.S. The focus areas are provided as geospatial data supported by tables that summarize what is known about the REE potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.H., and Dicken, C.L., 2019, Focus areas for data acquisition for potential domestic sources of critical minerals—Rare earth elements, chap. A of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals: U.S. Geological Survey Open-File Report 2019–1023, 11 p., https://doi.org/10.3133/ofr20191023A.

In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.) (https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf). Acquiring information on possible domestic sources of these critical minerals is the rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The first phase of Earth MRI focused on the study of rare-earth elements (REE) (https://pubs.er.usgs.gov/publication/ofr20191023A). Phase 2 version 2 (this report) focuses on the following minerals: aluminum, cobalt, graphite, lithium, niobium, platinum group elements (PGE), rare earth elements, tantalum, tin, titanium, and tungsten. The USGS has identified broad areas within the U.S. to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the U.S. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.M., and others (in review)

In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.) (https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf). Acquiring information on possible domestic sources of these critical minerals is the rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The first phase of Earth MRI focused on the study of rare-earth elements (REE) (https://pubs.er.usgs.gov/publication/ofr20191023A). Phase 2 version 2 (this report) focuses on the following minerals: aluminum, cobalt, graphite, lithium, niobium, platinum group elements (PGE), rare earth elements, tantalum, tin, titanium, and tungsten. The USGS has identified broad areas within the U.S. to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the U.S. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.M., and others (in review)

In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 36 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.) (https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf). Acquiring information on possible domestic sources of these critical minerals is the rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, Federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The USGS has identified broad areas within the United States to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the United States. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.M., Dicken, C.L., Woodruff, L.G., Andersen, A.K., Brennan, S., Day, W.C., Drenth, B.J., Foley, N.K., Hall, S., Hofstra, A.H., McCafferty, A.E., Shah, A.K., and Ponce, D.A., 2022, Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico—Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadium, and zirconium, chap. D of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals: U.S. Geological Survey Open-File Report 2019–1023, 65 p., https://doi.org/10.3133/ofr20191023D.

In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 36 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.) (https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf). Acquiring information on possible domestic sources of these critical minerals is the rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, Federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The USGS has identified broad areas within the United States to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the United States. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.M., Dicken, C.L., Woodruff, L.G., Andersen, A.K., Brennan, S., Day, W.C., Drenth, B.J., Foley, N.K., Hall, S., Hofstra, A.H., McCafferty, A.E., Shah, A.K., and Ponce, D.A., 2022, Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico—Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadium, and zirconium, chap. D of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals: U.S. Geological Survey Open-File Report 2019–1023, 65 p., https://doi.org/10.3133/ofr20191023D.

In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 36 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.) (https://pubs.usgs.gov/of/2018/1021/ofr20181021.pdf). Acquiring information on possible domestic sources of these critical minerals is the rationale for the USGS Earth Mapping Resources Initiative (Earth MRI). The program, which partners the USGS with State Geological Surveys, Federal agencies, and the private sector, aims to collect new geological, geophysical, and topographic (lidar) data in key areas of the U.S. to stimulate mineral exploration and production of critical minerals. The USGS has identified broad areas within the United States to target acquisition of geologic mapping, geophysical data, and (or) detailed topographic information to aid research, mineral exploration, and evaluation of mineral potential in these areas. Focus areas were defined using existing geologic data including data on known deposits in the United States. The focus areas are provided as geospatial data supported by tables that summarize what is known about the mineral potential and brief descriptions of data gaps that could be addressed by the Earth MRI program. A full discussion of Earth MRI and the rationale and methods used to develop the geospatial data are provided in the following report: Hammarstrom, J.M., Dicken, C.L., Woodruff, L.G., Andersen, A.K., Brennan, S., Day, W.C., Drenth, B.J., Foley, N.K., Hall, S., Hofstra, A.H., McCafferty, A.E., Shah, A.K., and Ponce, D.A., 2022, Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico—Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadium, and zirconium, chap. D of U.S. Geological Survey, Focus areas for data acquisition for potential domestic sources of critical minerals: U.S. Geological Survey Open-File Report 2019–1023, 65 p., https://doi.org/10.3133/ofr20191023D.

Version 4.0 of this data release provides descriptions of more than 200 mineral districts, mines, and mineral occurrences (deposits, prospects, and showings) within the United States that are reported to contain substantial enrichments of the rare earth elements (REEs). These mineral occurrences include mined deposits, exploration prospects, and other occurrences with notable concentrations of the REEs. The inclusion of a particular mineral occurrence in this database is not meant to imply that it has economic potential. Rather, these occurrences were included to capture the distribution and characteristics of the known, reported REEs deposits in the United States, which are diverse in their geology and resource potential. Concentrated, mineable deposits of the REEs are rare, such that most of the sites within this data release are for unmined locations where the published information may not contain thorough descriptions (Van Gosen and others, 2014). Therefore, decisions had to be made by the authors regarding the addition or exclusion of specific REE occurrences in the dataset, based principally on the available descriptions of the REE concentrations and the apparent size of the mineralized body. The level of detail of this type of information varied widely amongst the occurrences, ranging from general descriptions to detailed sampling and analysis of some deposits. The entries and descriptions in the database were derived from published papers, reports, data, and internet documents representing a variety of sources, including geologic and exploration studies described in State, Federal, and industry reports. Although an attempt was made to capture as many examples as possible, this dataset is a progress report that is part of an ongoing effort. The authors welcome additional published information in order to continually update and refine this dataset. In addition to the conventional resources described in this report, every year approximately 56,000 metric tons of REEs are mined, beneficiated, and put into solution, but not recovered, by operations associated with the global phosphate fertilizer industry (Emsbo and others, 2015, 2016). As indicated by Emsbo and others (2015, 2016), recovery of byproduct REEs from the phosphate industry has the potential to substantially increase the supply of REEs to the market. The significant increases in applications and demands for REEs has led to an increased interest in identifying new sources that include extraction not only from mineral deposits, but also the potential for REE extraction from coal-based resources, and recycling of products containing REEs. The Department of Energy is currently (2019) evaluating technologies to recover REEs and other critical minerals from coal and coal-based resources (https://www.netl.doe.gov/coal/rare-earth-elements). Recycling efforts have focused on recovering REEs from light bulbs and electronics. The dataset provided in this data release is restricted to non-fuel, REE-bearing mineral deposits and does not include energy resources (such as coal). Van Gosen, B.S., Verplanck, P.L., Long, K.R., Gambogi, Joseph, and Seal, R.R., II, 2014, The rare-earth elements—Vital to modern technologies and lifestyles: U.S. Geological Survey Fact Sheet 2014–3078, 4 p., https://dx.doi.org/10.3133/fs20143078. Emsbo, Poul, McLaughlin, P.I., Breit, G.N., du Bray, E.A., and Koenig, A.E., 2015, Rare earth elements in sedimentary phosphate deposits—Solution to the global REE crisis?: Gondwana Research, v. 27, p. 776–785, accessed March 13, 2019, at https://doi.org/10.1016/j.gr.2014.10.008. Emsbo, Poul, McLaughlin, P.I., du Bray, E.A., Anderson, E.D., Vandenbroucke, T.R.A., and Zielinski, 2016, Rare earth elements in sedimentary phosphorite deposits—A global assessment, chap. 5 of Verplanck, P.L, and Hitzman, M.W., eds., Rare earth and critical elements in ore deposits: Reviews in Economic Geology, v. 18, p. 101–114, accessed March 13, 2019, at

Version 4.0 of this data release provides descriptions of more than 200 mineral districts, mines, and mineral occurrences (deposits, prospects, and showings) within the United States that are reported to contain substantial enrichments of the rare earth elements (REEs). These mineral occurrences include mined deposits, exploration prospects, and other occurrences with notable concentrations of the REEs. The inclusion of a particular mineral occurrence in this database is not meant to imply that it has economic potential. Rather, these occurrences were included to capture the distribution and characteristics of the known, reported REEs deposits in the United States, which are diverse in their geology and resource potential. Concentrated, mineable deposits of the REEs are rare, such that most of the sites within this data release are for unmined locations where the published information may not contain thorough descriptions (Van Gosen and others, 2014). Therefore, decisions had to be made by the authors regarding the addition or exclusion of specific REE occurrences in the dataset, based principally on the available descriptions of the REE concentrations and the apparent size of the mineralized body. The level of detail of this type of information varied widely amongst the occurrences, ranging from general descriptions to detailed sampling and analysis of some deposits. The entries and descriptions in the database were derived from published papers, reports, data, and internet documents representing a variety of sources, including geologic and exploration studies described in State, Federal, and industry reports. Although an attempt was made to capture as many examples as possible, this dataset is a progress report that is part of an ongoing effort. The authors welcome additional published information in order to continually update and refine this dataset. In addition to the conventional resources described in this report, every year approximately 56,000 metric tons of REEs are mined, beneficiated, and put into solution, but not recovered, by operations associated with the global phosphate fertilizer industry (Emsbo and others, 2015, 2016). As indicated by Emsbo and others (2015, 2016), recovery of byproduct REEs from the phosphate industry has the potential to substantially increase the supply of REEs to the market. The significant increases in applications and demands for REEs has led to an increased interest in identifying new sources that include extraction not only from mineral deposits, but also the potential for REE extraction from coal-based resources, and recycling of products containing REEs. The Department of Energy is currently (2019) evaluating technologies to recover REEs and other critical minerals from coal and coal-based resources (https://www.netl.doe.gov/coal/rare-earth-elements). Recycling efforts have focused on recovering REEs from light bulbs and electronics. The dataset provided in this data release is restricted to non-fuel, REE-bearing mineral deposits and does not include energy resources (such as coal). Van Gosen, B.S., Verplanck, P.L., Long, K.R., Gambogi, Joseph, and Seal, R.R., II, 2014, The rare-earth elements—Vital to modern technologies and lifestyles: U.S. Geological Survey Fact Sheet 2014–3078, 4 p., https://dx.doi.org/10.3133/fs20143078. Emsbo, Poul, McLaughlin, P.I., Breit, G.N., du Bray, E.A., and Koenig, A.E., 2015, Rare earth elements in sedimentary phosphate deposits—Solution to the global REE crisis?: Gondwana Research, v. 27, p. 776–785, accessed March 13, 2019, at https://doi.org/10.1016/j.gr.2014.10.008. Emsbo, Poul, McLaughlin, P.I., du Bray, E.A., Anderson, E.D., Vandenbroucke, T.R.A., and Zielinski, 2016, Rare earth elements in sedimentary phosphorite deposits—A global assessment, chap. 5 of Verplanck, P.L, and Hitzman, M.W., eds., Rare earth and critical elements in ore deposits: Reviews in Economic Geology, v. 18, p. 101–114, accessed March 13, 2019, at